The pregnant women faces a unique physiological challenge to reorganize the maternal uterine vascular network to accommodate the metabolic demands of the feto-placental and uteroplacental blood flow by angiogenic growth factors (with particular focus on bFGF and VEGF) and the vascular regulator nitric oxide. This grant has two overall Specific Aims: 1) to establish molecular and cellular models of the regulation of the vascular endothelium at the maternal-fetal interface; and 2) to investigate these basic mechanisms in clinical settings where changes in placental regulator factors are hypothesized to control vascular adaptation to pregnancy. To accomplish these overall Aims, we propose four integrated projects, two scientific cores, and one administrative core. Our first Aim will primarily be addressed by the first two projects: Project I: Signaling mechanisms controlling NO production and mitogenesis in Uterine Artery Endothelial Cells (UAEC) and Ovine Fetal Placental Artery Endothelial Cells (OFPAEC). Project II: Angiogenic factor (bFGF and VEGF) and shear stress mediated changes in placental and uterine artery nitric oxide production. In these two highly integrated projects, we will utilize well-established cell lines and experimental systems derived by the project leaders from pregnant sheep. We will identify in vitro the signaling pathways used by angiogenic factors as well as their modulation by pregnancy, and address the mechanisms by which flow/shear stress mediate changes in endothelial cell expression of eNOS and NO production. In parallel to these basic studies, we propose two projects to address how pathophysiological perturbation of angiogenic control contributes significantly to the degradation of fetal health and well-being. Project III: Ethanol exposure on nitric oxide production and angiogenesis in the human placenta. Project IV: Trophoblast regulation of angiogenesis in the diabetic placenta. In these two highly integrated projects, we will utilize established endothelial cell lines and experimental systems derived by the project leaders from pregnant sheep. We will identify in vitro the signaling pathways used by angiogenic factors as well as their modulation by pregnancy, and address the mechanisms by which flow/shear stress mediated changes in endothelial cell expression of eNOS and NO production. In parallel to these basic studies, we propose two projects to address how pathophysiological perturbation of angiogenic control contributes significantly to the degradation of fetal health and well-being. Project III: Ethanol exposure on nitric oxide production and angiogenesis in the human placenta. Project IV: Trophoblast regulation of angiogenesis in the diabetic placenta. Ultimately, Projects III and IV will converge with Projects I and II, in that intracellular signaling mechanisms uncovered in the latter can be explored as the underlying causes of pathophysiological changes in the former clinical settings. The overall goals and integrated operation of the four Projects will be assured by the Administrative Core, and through usage of standardized assays and methods in all four Projects of Experimental Cores, Molecular Culture/Angiogenesis. Data from these studies will further our understanding of the basic control of placental and uterine angiogenesis and mechanisms contributing to fetal pathophysiology in diabetes, ethanol exposure, as well as pre-eclampsia and IUGR.